♻️ refactor: update codebase #2

Author: pnguyen215

docs/GETTING_STARTED.md

@@ -1892,10 +1892,10 @@ var startOfEpoch = timefy.MustParse("2020-01-01")
 
 ## 24. Enterprise Use Cases
 
-The `_example/` directory contains five complete, runnable enterprise programs
+The `examples/` directory contains five complete, runnable enterprise programs
 that demonstrate production-grade patterns.
 
-### `_example/billing/` — SaaS Subscription Billing
+### `examples/billing/` — SaaS Subscription Billing
 
 **Business problem:** A multi-tenant SaaS platform bills customers monthly,
 quarterly, and annually.  Customers sign up mid-period and receive pro-rated
@@ -1918,10 +1918,10 @@ charges.  Some plans include a free trial period.
 | `DurationInDays` | Pro-rate day counting |
 
 ```bash
-cd _example/billing && go run main.go
+cd examples/billing && go run main.go
 ```
 
-### `_example/global_team/` — Multi-Timezone Team Coordination
+### `examples/global_team/` — Multi-Timezone Team Coordination
 
 **Business problem:** An engineering organization spans five cities.  The
 platform must find meeting overlap windows, detect business-hour availability,
@@ -1940,10 +1940,10 @@ and generate cross-team working-day schedules that respect public holidays.
 | `New(t).TimeAgo()` / `TimeUntil()` | Release timeline display |
 
 ```bash
-cd _example/global_team && go run main.go
+cd examples/global_team && go run main.go
 ```
 
-### `_example/audit/` — Enterprise Audit Trail & Compliance
+### `examples/audit/` — Enterprise Audit Trail & Compliance
 
 **Business problem:** A financial services platform records all data-access
 events, enforces GDPR Article 33 (72-hour breach notification), detects SLA
@@ -1965,10 +1965,10 @@ breaches for support tickets, and generates CISO reports.
 | `New(t).TimeAgo()` | Human-readable event age |
 
 ```bash
-cd _example/audit && go run main.go
+cd examples/audit && go run main.go
 ```
 
-### `_example/reporting/` — Financial Quarter & Fiscal-Year Reporting
+### `examples/reporting/` — Financial Quarter & Fiscal-Year Reporting
 
 **Business problem:** A publicly-traded company needs precise SEC filing
 windows, YTD periods, QoQ comparisons, and a July-1-start fiscal year
@@ -1991,10 +1991,10 @@ calendar.
 | `New(t).Quarter()` | Quarter number label |
 
 ```bash
-cd _example/reporting && go run main.go
+cd examples/reporting && go run main.go
 ```
 
-### `_example/scheduler/` — Business-Day-Aware Job Scheduler
+### `examples/scheduler/` — Business-Day-Aware Job Scheduler
 
 **Business problem:** A financial data platform schedules ETL jobs on daily,
 monthly, and quarterly boundaries, ensuring jobs fire only on business days and
@@ -2017,7 +2017,7 @@ are not duplicated within a configurable time window.
 | `New(t).TimeAgo()` / `TimeUntil()` | Last-ran / next-run display |
 
 ```bash
-cd _example/scheduler && go run main.go
+cd examples/scheduler && go run main.go
 ```
 
 ---

examples/audit/main.go

@@ -12,7 +12,7 @@
 //
 // Run with:
 //
-//	cd _example/audit && go run main.go
+//	cd examples/audit && go run main.go
 package main
 
 import (
@@ -35,19 +35,19 @@ const (
 
 // AuditEvent is a single immutable audit record.
 type AuditEvent struct {
-	ID          string
-	OccurredAt  time.Time // stored in UTC, nanosecond precision
-	ActorID     string
-	Action      string
-	Resource    string
-	Severity    Severity
-	Resolved    bool
-	ResolvedAt  time.Time // zero value if unresolved
+	ID         string
+	OccurredAt time.Time // stored in UTC, nanosecond precision
+	ActorID    string
+	Action     string
+	Resource   string
+	Severity   Severity
+	Resolved   bool
+	ResolvedAt time.Time // zero value if unresolved
 }
 
 // HourBucket groups audit events that occurred within the same UTC hour.
 type HourBucket struct {
-	Hour   time.Time    // beginning of the hour (UTC)
+	Hour   time.Time // beginning of the hour (UTC)
 	Events []AuditEvent
 }
 
@@ -59,6 +59,7 @@ type HourBucket struct {
 //   - Using time.Add(72 * time.Hour) is equivalent here, but AddHour reads as
 //     intent-revealing code in an audit context where "hours" is the business
 //     unit mandated by law.
+//
 // ─────────────────────────────────────────────────────────────────────────────
 func gdprBreachDeadline(detectedAt time.Time) time.Time {
 	return timefy.AddHour(detectedAt, 72)
@@ -87,6 +88,7 @@ func isGDPRCompliant(detectedAt, reportedAt time.Time) bool {
 //   - SLAs in enterprise support contracts only count working hours.
 //     A ticket created at 17:00 Friday with a 4-hour SLA should expire at
 //     13:00 Monday, not 21:00 Friday (which would already be closed).
+//
 // ─────────────────────────────────────────────────────────────────────────────
 func slaDeadline(createdAt time.Time, businessHours int) time.Time {
 	cursor := createdAt

examples/billing/main.go

@@ -7,7 +7,7 @@
 //
 // Run with:
 //
-//	cd _example/billing && go run main.go
+//	cd examples/billing && go run main.go
 package main
 
 import (

examples/global_team/main.go

@@ -13,7 +13,7 @@
 //
 // Run with:
 //
-//	cd _example/global_team && go run main.go
+//	cd examples/global_team && go run main.go
 package main
 
 import (

examples/reporting/main.go

@@ -11,7 +11,7 @@
 //
 // Run with:
 //
-//	cd _example/reporting && go run main.go
+//	cd examples/reporting && go run main.go
 package main
 
 import (

examples/scheduler/main.go

@@ -14,7 +14,7 @@
 //
 // Run with:
 //
-//	cd _example/scheduler && go run main.go
+//	cd examples/scheduler && go run main.go
 package main
 
 import (